Your robot stand-in has arrived

Meet TIPI, the Telepresence Interface by Pendulum Inversion. TIPI is something of a surrogate, giving physical presence to telecommuters by balancing an LCD screen and camera atop its six foot frame. The user has full control of the robot’s movement, with their own camera image shown on the display so that others interacting with the bot will with whom they are conversing.

A pair of 12.5″ wheels connec to DC motors via a gear box with a 37:1 ratio. These specs are necessary to recover from a sudden 20 degree loss of equilibrium, quite impressive for a bot of this stature. An Orangutan SVP board monitors a two-axis accelerometer and a gyroscope for accurate positioning data. This board automatically keeps balance, while taking user commands from a second control, a Beagle Board. The Beagle Board handles the communications, including sending and receiving the video signals, and delivering incoming position control data to the Orangutan. Separating the two systems guards against a screen-shattering fall by making sure the hardware likely to face slow-down or lockup is physically separate from that responsible for balance.

the centre of mass being further from the wheels means it has a higher moment of inertia around those wheels, so it’ll accelerate less easily than if the lead acid battery was at the wheels, so it actually helps active stabilisation, even though it makes it less statically stable. You can see this by trying to balance a broom handle or similar upright on your hand. It’s easier with a longer pole.

Looks nice, but almost like they tried to put too much stuff into one package. Having it self balancing is a neat technical accomplishment, but it doesn’t appear to do anything but make the robot super wobbly. Mechanically, it is again impressive but ultimately overkill: if it didn’t have to worry about balancing itself a much simpler drive system could have had similar, if not better, performance. And then it’s like they ran out of time or energy to add things that would have made a big difference, such as the ability to control it wirelessly over the internet.
Sorry don’t mean to get too down on this, it looks like a great technology demonstration by the student team. Just not super practical.

“Unfortunately. the University network blocked and throttled all of our internet communication sofware so we were forced to hack together a wired solution during the first 30 minutes of our symposium. This is why the monitor is just showing what the webcam is looking at.” – patfairbank.com/tipi

@Alex
The video’s description says it does work over Wifi/internet, but the network at the demo site wasn’t up to it.
As for the inverted pendulum setup, I expect it makes it far less likely to topple over during braking/acceleration than a non-balancing bot, and it can brake/accelerate at the maximum dV/dt the layout allows.
Once the controller is tuned properly that is… otherwise you’re going to need lots of spare LCDs :D

@ Jonathan
They got the balancing to work properly at 12am before the presentation. A day before that it would only balance for about a minute before becoming unstable, and a day before that it wouldn’t balance at all.

It only fell twice during the 5 hour presentation, and they never had to replace the LCD.